1. Field of the Invention
The present invention relates to an electronic apparatus and more particularly, to an electronic apparatus performing various calculations based on input data and outputting results by moving the decimal point by a predetermined digit.
2. Related Background Art
Various specific calculation and output modes are employed for a known electronic desk type calculator (hereinafter referred to as electronic calculator) for practical applications. A so-called add-mode automatically moving a decimal point is known, which is particularly useful for calculating with respect to dollars and cents.
When a calculation of the amount of money, including different monetary units such as dollars and cents, is performed, a decimal point is automatically inserted between the different monetary units in the add-mode. The lower two digits of a number including monetary units of dollars and cents are considered as cents and a decimal point is automatically inserted in front of the lower two digits.
For example, in summing 1 dollar and 23 cents with 4 dollars and 56 cents, keys "1", "2", "3", "+", "4", "5", "6" and "=" are pressed in this order. Decimal points are automatically inserted in front of the lower two digits so that "5.79" indicating 5 dollars and 79 cents is output. The operational procedure for this is as shown in Table 1.
TABLE 1 ______________________________________ (Addition in Conventional Add-Mode) No. Key Operation Output ______________________________________ ##STR1## 1.23 2 ##STR2## 1.23 3 ##STR3## 4.56 4 ##STR4## 5.79 ______________________________________
By using the add-mode, it is convenient in that decimal points are not needed to be entered by pressing the corresponding key.
The conventional add-mode function is effective for the addition and subtraction operations and it not executed for the multiplication and division operations or, when it is executed, a first registration number (dividend or multiplicand) is divided by 100 (in case of two digits shift) and a second registration number (divisor or multiplier) is subject to calculation without a decimal point shift. The reason for this is that multipliers or divisors used in calculating the amount of money are seldom in term of money amount. For instance, in calculating the sun of money for buying five goods each amounting 1 dollar and 23 cents, keys "1", "2", "3", "x", "5" and "=" are pressed in this order to first move the decimal point of the first registration number by two digits and then perform a calculation using the second registration number without performing a decimal point shift. As a result, "6.15" indicating 6 dollars and 15 cents is output. The operational procedure for this is as shown in Table 2.
TABLE 2 ______________________________________ (Multiplication in Conventional Add-Mode) No. Key Operation Output ______________________________________ ##STR5## 1.23 2 ##STR6## 1.23 3 ##STR7## 5 4 ##STR8## 6.15 ______________________________________
In case of division, the similar operations are performed without shifting the decimal point of the second registration number.
However, if the conventional electronic calculator is set at an add-mode and used for identical number calculations, the decimal point shift is not carried out. As is well known, in the identical number calculation, the calculation mode (designated by calculation key) and the second (or first) registration number immediately before the calculation are stored. Thereafter, the first (second) registration number is entered following depression of an equal "=" key functioning as a calculation result output key, to thereby perform addition, subtraction, multiplication or division using identical numbers. For instance, in calculating the amount of money which each one of three persons must pay for a purchase amounting 3 dollars and 69 cents, keys "3", "6", "9", "/", "3" and "=" are pressed in this order to accordingly obtain a solution "1.23". After this calculation, the second registration number, in this case the identical number "3", and the division calculation mode are stored. However, in case where the next identical number calculation for a next purchase, e.g., division of 5 dollars and 64 cents by the identical number "3", is necessary, the conventional electronic calculator cannot perform a decimal point shift in the add-mode. For instance, even if keys "5", "6", "4" and "=" are entered, this input is not considered as an input in the add-mode, but an ordinary calculation of "564/3" is performed and "188.00" is output. The operational procedure for this is as shown in Table 3.
TABLE 3 ______________________________________ (Identical Number Division in Conventional Add-Mode) No. Key Operation Output Note ______________________________________ ##STR9## 3.69 (Add-Mode) 2 ##STR10## 3.69 3 ##STR11## 3 (Identical Number) 4 ##STR12## 1.23 5 ##STR13## 564 6 ##STR14## 188.00 (.div. Identical Number) ______________________________________
Therefore, it is necessary to enter the entire keys including the identical number or to divide the calculation result by 100, resulting in a disadvantage of cumbersome operations and of multiple operation procedures.